Vehicle doors are typically constructed of two or more panels attached to a door frame, including a sheet metal outer panel that defines the door's exterior and a sheet metal inner panel secured to the door frame. Various door components are affixed to the door frame, including a window and window regulator, audio speakers, door locks, latches, and the like. A trim panel is fastened to the inner door panel to present an aesthetically pleasing appearance in the occupant compartment and to hide the internal components of the door assembly.
To lessen the effects of a side impact type collision on the vehicle occupant seating area, some vehicle door assemblies may include a door intrusion guard beam, side bolsters of foam or honeycomb construction, or other body side structural upgrades. Positioning of these devices also depends on the specific vehicle door design, but takes into account the special relationship of an occupant seating area adjacent the door. A side impact collision may cause localized deformation of the door, forcing the door and/or trim panel into the occupant seating area.